[build] Don't define a package() target

package() targets should not be used for plain shared libraries.
Nothing depends on this package() target any more, so remove it.

Change-Id: I56d04c2bd1e9a97e4639c291faafb7fdd207265f
diff --git a/BUILD.gn b/BUILD.gn
index 9818f21..6cef35a 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -26,8 +26,6 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-import("//packages/package.gni")
-
 config("zlib_config") {
   include_dirs = [ "." ]
 }
@@ -104,24 +102,3 @@
   configs -= [ "//build/config:symbol_visibility_hidden" ]
   public_configs = [ ":zlib_config" ]
 }
-
-package("package") {
-  system_image = true
-
-  package_name = "zlib"
-
-  deps = [
-    ":minizip",
-    ":zlib",
-  ]
-
-  libraries = [
-    {
-      name = "libz.so"
-    },
-
-    {
-      name = "libminizip.so"
-    },
-  ]
-}